Seismic Upgrading of a Masonry Church with FRP Composites

2016 ◽  
Vol 866 ◽  
pp. 119-123 ◽  
Author(s):  
Gabriele Milani ◽  
Rafael Shehu ◽  
Marco Valente
Keyword(s):  
Seismic Performance ◽  
Fiber Reinforced Polymers ◽  
Seismic Action ◽  
Structural Elements ◽  
Lateral Loads ◽  
Reinforced Polymers ◽  
Preliminary Results ◽  
Existing Structures ◽  
Frp Composites ◽  
The Church

This paper presents some preliminary results of seismic analyses performed on a masonry church located in Emilia-Romagna (Italy). The church suffered damage during the seismic events occurred in 2012 and some seismic upgrading interventions by means of Fiber Reinforced Polymers (FRPs) are proposed. The behavior of the church is investigated under horizontal loads simulating a seismic action defined in accordance with Italian Code indications. The preliminary results of the numerical analyses performed on the church in the unretrofitted configuration put in evidence both the insufficient strength of some structural elements when subjected to lateral loads and a typical failure mode of the façade. Two seismic upgrading interventions with FRP composites are simulated in order to increase the seismic performance of the church. Such interventions are carried out according to the provisions of Italian Code for FRP strengthening of existing structures. Numerical results show that a proper seismic upgrading intervention by means of FRP composites is effective to improve the seismic performance of the church.

scholarly journals New Model Of Enhanced Plasticity For Reinforced Concrete Structural Elements That Take Into Account The Effects Of Lateral Loading And Gravity

2021 ◽  
Vol 12 (2) ◽  
pp. 1482-1487
Author(s):  
P Venkat Ram Reddya, Et. al.
Keyword(s):  
Reinforced Concrete ◽  
Structure Type ◽  
Fiber Reinforced Polymers ◽  
Structural Elements ◽  
Structural Components ◽  
Reinforced Polymers ◽  
Primary Motivation ◽  
Existing Structures ◽  
Wide Range ◽  
Frp Retrofit

Reinforced concrete structures are exposed to a progression of activities all through their life expectancy which may be the purpose behind damage. Subsequently, rehabilitation of existing structures is typically performed either to restore structural limit because of decay or damage or to broaden existing structural limit due to expanded loads. To fortify existing structures, numerous new creative materials like progressed fiber-reinforced polymers (FRPs) are discovered to be acceptable substitute for reinforcing materials like steel. They are actualized to fortify the presentation of structural components in flexure, pivotal, shear, and twist. In a RC outline, migrating plastic pivots in the beam off from the column face is normally prescribed to broaden pliability of the edge. This could be accomplished through rib reinforced FRP retrofit of the joint. Furthermore, to it, thus we execute an expanded pliancy for the concrete structural components like column, beam, chunk, dividers then on. The primary motivation behind a wide range of structural frameworks utilized in the structure type of structures is to transfer gravity and horizontal loads effectively.

scholarly journals Bond between Concrete and Multi-Directional CFRP Laminates

2010 ◽  
Vol 133-134 ◽  
pp. 917-922 ◽  
Author(s):  
José Sena-Cruz ◽  
Joaquim Barros ◽  
Mário Coelho
Keyword(s):  
Carbon Fiber ◽  
Civil Engineering ◽  
Fiber Reinforced Polymers ◽  
Structural Elements ◽  
Engineering Applications ◽  
Carbon Fiber Reinforced Polymers ◽  
Reinforced Polymers ◽  
Cfrp Laminate ◽  
Cfrp Laminates ◽  
Pullout Tests

Recently, laminates of multi-directional carbon fiber reinforced polymers (MDL-CFRP) have been developed for Civil Engineering applications. A MDL-CFRP laminate has fibers in distinct directions that can be arranged in order to optimize stiffness and/or strength requisites. These laminates can be conceived in order to be fixed to structural elements with anchors, resulting high effective strengthening systems. To evaluate the strengthening potentialities of this type of laminates, pullout tests were carried out. The influence of the number of anchors, their geometric location and the applied pre-stress are analyzed. The present work describes the carried-out tests and presents and analyzes the most significant obtained results.

scholarly journals Behavior of Columns Confined With FRP Fabrics under Repeated Lateral Loads

2019 ◽  
pp. 1-19
Author(s):  
Hesham A. Haggag ◽  
Nagy F. Hanna ◽  
Ghada G. Ahmed
Keyword(s):  
Reinforced Concrete ◽  
Carbon Fiber ◽  
Axial Load ◽  
Axial Loading ◽  
Concrete Columns ◽  
Fiber Reinforced Polymers ◽  
Lateral Loads ◽  
Reinforced Concrete Columns ◽  
Reinforced Polymers ◽  
Axial Capacity

The axial strength of reinforced concrete columns is enhanced by wrapping them with Fiber Reinforced Polymers, FRP, fabrics.  The efficiency of such enhancement is investigated for columns when they are subjected to repeated lateral loads accompanied with their axial loading.  The current research presents that investigation for Glass and Carbon Fiber Reinforced Polymers (GFRP and CFRP) strengthening as well.  The reduction of axial loading capacity due to repeated loads is evaluated. The number of applied FRP plies with different types (GFRP or CFRP) are considered as parameters in our study. The study is evaluated experimentally and numerically.  The numerical investigation is done using ANSYS software. The experimental testing are done on five half scale reinforced concrete columns.  The loads are applied into three stages. Axial load are applied on specimen in stage 1 with a value of 30% of the ultimate column capacity. In stage 2, the lateral loads are applied in repeated manner in the existence of the vertical loads.  In the last stage the axial load is continued till the failure of the columns. The final axial capacities after applying the lateral action, mode of failure, crack patterns and lateral displacements are recorded.   Analytical comparisons for the analyzed specimens with the experimental findings are done.  It is found that the repeated lateral loads decrease the axial capacity of the columns with a ratio of about (38%-50%).  The carbon fiber achieved less reduction in the column axial capacity than the glass fiber.  The column confinement increases the ductility of the columns under the lateral loads.

scholarly journals In Plane Cyclic Behavior of Masonry Walls Jacketed with Fiber Reinforced Mortar and Fiber Grids

2013 ◽  
Vol 9 (3) ◽  
pp. 32-39 ◽  
Author(s):  
Viorel Popa ◽  
Radu Pascu ◽  
Andrei Papurcu
Keyword(s):  
Experimental Research ◽  
Research Program ◽  
Fiber Reinforced Polymers ◽  
Cyclic Behavior ◽  
Masonry Walls ◽  
Seismic Action ◽  
Fiber Reinforced ◽  
Building Stock ◽  
Reinforced Polymers ◽  
Displacement Capacity

Abstract Masonry buildings represent the most vulnerable part of the building stock to seismic action in Romania. The main goal of this experimental research program is to investigate the efficiency of several retrofitting solutions using fiber reinforced polymers. Research focused on the lateral strength and displacement capacity of the retrofitted specimens. The masonry walls were built using solid bricks. Glass or carbon fiber reinforced polymers (GFRP or CFRP) embedded in a fiber reinforced mortar layer were used for jacketing. Seven specimens having essentially 25cm width, 1,75m height and 2,10m length were tested in the experimental research program. These specimens were subjected to a constant vertical compressive stress of 1,2MPa. A quasi-static load protocol was considered for the horizontal loading. This paper presents the layout of the experimental research program and some preliminary results.

scholarly journals FRP REINFORCEMENT FOR CONCRETE STRUCTURES: STATE-OF-THE-ART REVIEW OF APPLICATION AND DESIGN

2014 ◽  
Vol 5 (4) ◽  
pp. 147-158 ◽  
Author(s):  
Eugenijus Gudonis ◽  
Edgaras Timinskas ◽  
Viktor Gribniak ◽  
Gintaris Kaklauskas ◽  
Aleksandr K. Arnautov ◽  
...  
Keyword(s):  
Material Properties ◽  
Structural Engineering ◽  
State Of The Art ◽  
Concrete Structures ◽  
Fiber Reinforced Polymers ◽  
Reinforced Polymers ◽  
Promising Alternative ◽  
Frp Composites ◽  
Structural Problems ◽  
Concrete Elements

Fiber reinforced polymers (FRPs) are considered to be a promising alternative to steel reinforcement, especially in concrete structures subjected to an aggressive environment or to the effects of electromagnetic fields. Although attempts to develop effective reinforcement have been followed, the application of FRPs remains limited by the solution to simple structural problems that mainly appear due to the absence of design codes, significant variation in the material properties of FRP composites and limited knowledge gained by engineers as regards the application aspects of FRP composites and structural mechanics of concrete elements reinforced with FRPs. To fill the latter gap, the current state-of-the-art report is dedicated to present recent achievements in FRPs applying practice to a broad engineers’ community. The report also revises the manufacturing process, material properties, the application area and design peculiarities of concrete elements reinforced with FRP composites. Along the focus on internal reinforcement, the paper overviews recent practices of applying FRP reinforced concrete (RC) elements in structural engineering. The review highlights the main problems restricting the application of FRPs in building industry and reveals the problematic issues (related to the material properties of the FRP) important for designing RC following the formulation of targets for further research.

An Eulerian Orthogonal Cutting Model for Unidirectional Fiber-Reinforced Polymers

2018 ◽  
Vol 140 (2) ◽  
Author(s):  
Shengqi Zhang ◽  
John S. Strenkowski
Keyword(s):  
Cutting Forces ◽  
Orthogonal Cutting ◽  
Damage Model ◽  
Subsurface Damage ◽  
Fiber Reinforced Polymers ◽  
Fiber Reinforced ◽  
Reinforced Polymers ◽  
Unidirectional Fiber ◽  
Frp Composites ◽  
Cutting Model

An Eulerian model is described that simulates orthogonal cutting of unidirectional fiber-reinforced polymer (FRP) composites. The continuous finite element method (FEM) and the discontinuous Galerkin (DG) method are combined to solve the governing equations. A progressive damage model is implemented to predict subsurface damage in the composite. A correction factor that accounts for fiber curvature is included in the model that incorporates the influence of fiber bending. It was found that fiber orientation has a dominant influence on both the cutting forces and subsurface damage. Good agreement was found between predicted cutting forces and subsurface damage and published experimental observations.

scholarly journals Thermomechanical Characterization of CFRPs under Elevated Temperatures for Strengthening Existing Structures

Fibers ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 80
Author(s):  
Christina Papadimitriou ◽  
Lazaros Melidis ◽  
Lambros Kotoulas ◽  
Nikolaos Makris ◽  
Konstantinos Katakalos
Keyword(s):  
Thermal Loading ◽  
Elevated Temperatures ◽  
Tensile Load ◽  
Concrete Columns ◽  
Fiber Reinforced Polymers ◽  
Reinforced Polymers ◽  
Existing Structures ◽  
Structural Reinforcement ◽  
Constant Tensile Load

Fiber-reinforced polymers (FRP) are rapidly gaining acceptance from the construction sector due to their large effectiveness. They are mainly used as confining reinforcement for concrete columns and as tensile reinforcement for concrete beams, columns and slabs. FRPs are already used to a large extent for applications such as bridges and parking lots, where elevated temperatures are not the main risk. Their increasing use as structural reinforcement is hampered by the concern related to their behavior at elevated temperatures as the relevant research is deficient. Thanks to the significant advantage of FRPs’ mechanical properties, further investigation into the influence of heating on their mechanical behavior may solve many doubts. The present study examines the influence of temperatures, ranging among 50, 100 and 250 °C, on the tensile strength of FRP laminates with carbon fibers (CFRP). In addition, the resistance of CFRP specimens to low-cycle thermal loading at the temperatures of 50, 100 and 250 °C under constant tensile load was investigated. The experiments were carried out in the laboratory of Experimental Strength of Materials and Structures of Aristotle University of Thessaloniki.

Fiber Reinforced Polymers in Civil Engineering: Durability Issues

2015 ◽  
Vol 1129 ◽  
pp. 283-289
Author(s):  
Mariaenrica Frigione
Keyword(s):  
Current Literature ◽  
Civil Engineering ◽  
Experimental Studies ◽  
Critical Issue ◽  
Fiber Reinforced Polymers ◽  
Fiber Reinforced ◽  
Thermosetting Resins ◽  
Reinforced Polymers ◽  
Frp Composites ◽  
Environmental Agents

In the last decades, the use of fiber reinforced polymers (FRP) composites to repair and/or upgrade existing buildings or infrastructure systems proved to be an effective solution, being able to overcome some of the drawbacks experienced with traditional interventions. The knowledge of durability behavior of polymer composite materials in terms of their degradation/aging causes and mechanisms is a critical issue for a safe and advantageous implementation of FRP. The durability of FRP employed in civil infrastructure applications mainly depends on the durability of any single component and on the environment (service conditions) in which the system operates. The components of FRP are: polymeric resins (more frequently thermosetting resins cured in service, i.e. at ambient temperature), fibers and the interface between them. Referring to the resins, heavy concerns arise from the behavior of “Cold-cured” thermosetting resins, often epoxy, used as matrices to manufacture (through wet layup technique) and adhesives to apply, also precured, FRP. The experimental studies present in current literature on the effect of environmental agents on the properties of FRP highlight the crucial role of the adhesive/matrix on the behavior of the whole system. Many other parameters (i.e. direction and disposition of fibers, direction of load application) are involved in the assessment of the durability of FRP. However, in the durability studies of FRP and their components, a lack of specific standards for such materials is recognized. In addition, the results of durability studies do not always agree, possibly due to different curing/conditioning conditions employed. The aim of this work is to critically illustrate the durability studies carried out on FRP for civil engineering applications and appeared in current literature, highlighting the issues that are not yet assessed and addressed.

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